Transmission control



Dec. 16, 1952 o. w. scHoTz TRANSMISSION CONTROL 2 SHEETS-SHEET 1 FiledJuly 51, 1946 JNVENTOR. ozio mwz=z Dec. 16, 1952 o. w. SCHOTZ 1,TRANSMISSION CONTROL Filed July 31. 1946 2 SHEETS-SHEET 2 INVENTOR- OfiaH4 5 %022.

Patented Dec. 16, 1952 2&21533 2,621,533 TRANSMISSION CGNIROL Otto w.Schlitz, Detroit, Mich, assignor to Chrysler Corporation, Highland Park,Mich, a

corporation of Delaware Application July 31, 1946, Serial No. 687,247

Claims.

This invention relates to automotive Vehicle transmission controls andmore particularly to a means for imparting a resiliency to the mechanismadapted to transmit impulses from a control apparatus to a means forvarying the speed ratio drive of a transmission.

Apparatuses for automatically changing speed ratio drives in motorvehicle transmissions have been developed. These apparatuses are usuallyresponsive to driver signal as, for example, by throttle closing withinpredetermined vehicle speed limits to initiate a cycle including achange in transmission speed ratio drive. The transmissions usually haveincorporated therein a synchronizer, one type of which is illustratedand described in Patent 'No. 2,238,723 issued to O. E. Fishburn on April15, 1941. A fast, non-yielding application of force to the controls ofsuch transmissions is undesirable as the synchronizers require a timeinterval in which to operate and in automatic control systems it hasbeen found necessary to incorporate a means for rendering theapplication of force to the transmission control lever somewhat yieldingin nature. In addition the cycle in some apparatuses also includes adisengagement and reengagement of a clutch connecting the vehicle enginewith the transmission. In these apparatuses it is imperative that theclutch disengagment be assured before the change in transmission speedratio drive is forced. The use of a resilient linkage operativelyconnected between the prime mover of an automatic control system and thetransmission shiftable members, permits the force applied to thesemembers to be temporarily stored in the resilient linkage until theclutch is disengaged and thereby the synchronizer tooth pressure isreduced and the synchronizLers effort to align its teeth is not resistedby the vehicle engine torque.

It is usual to provide manual means for operating the clutch andchanging the transmission speed ratio drive. The device to be describedherein is adapted to transmit manual signals to the transmission andby-pass the resilient linkage.

It is a further object of the invention to provide a device for thispurpose having a minimum thickness.

The invention will be described herein in conjunction with a suggestedtransmission and clutch control apparatus as a typical applicationthereof although it is not intended that the invention be limited to theassociated apparatus described herein.

In the drawings:

Fig. 1 is a diagrammatic view of a transmission and clutch controlapparatus of which my invention forms a component part;

Fig. 2 is a side view of my device partly in section; and d Fig. 3 is afront elevation of my device.

Referring to Fig. 1 the transmission and clutch control apparatus willbe described. A transmission housing ]9 for a standard transmissionhaving three forward speeds and a reverse speed is illustrated asconnecting driving shaft 8 and driven shaft 9. Housing In has a selectorlever l I and shift lever l2 pivotally mounted thereon. The fluidcoupling 6 and clutch l op'eratively connected to the shaft 8, are shownin conjunction with clutch pedal l3 and clutch throw-out fork l4.Accelerator pedal i5, and carburetor [6 having throttle lever llrotatably mounted thereon are also illustrated. The housing It for thesteering column is shown supporting a manual shift control rod 19 bybracket 26}.

Manual means are provided in the apparatus illustrated in Fig. 1 for theoperation (if the clutch and control of the transmission speed ratiodrive. The clutch pedal 13 is rotatably mounted at 2! on a shaft (notshown). An extension i3' of clutch pedal [3 depends below rotatablemounting 2i and has fixed thereto a pin 22. A torque shaft 23 has oneend thereof rotatably mounted on the vehicle frame (not shown) and theother end rotatably mounted adjacent the engine block (not shown) in amanner well known in the art. .A collar 24 is rotatably mounted ontorque shaft 23. A pair of lugs 25 and 26 extending from collar 2dnormal to the axis thereof form levers by which rotation of collar 2e onshaft 23 i induced and transmitted to the clutch throw-out fork Hi. Lug26 has pivotally connected thereto a rod 21 which has a slot 28 in itsopposite end. Pin 22 of clutch pedal l3 cooperates with slot 28 to forma connection which will cause counterclockwise rotation of collar 24when clutch pedal i3 is rotated counterclockwise but will permit motionof collar 24 independently of pedal It, as an incident to automaticcontrol to be described herein. A rod 29 operatively connects lug 25with the clutch throw-out fork Hi. It is, therefore, evident that whenthe vehicle driver depresses pedal l3 rod 21 is pulled to the right inFig. 1 thereby rotating collar 24 in a counterclockwise direction andthrough leg' 25 and rod 29 the cluch throwout fork i l is rotated aboutits conventional pivot M to disengage the clutch. h I d The manual shiftcontrol rod I9 is slidably mounted in bracket 20 and adapted for bothaxial and rotary movement. As is usual in the art, the axial movement isadapted to select the cohveri: tional transmission shift rail which isto be moved and rotation thereof slides the shift rail in ile of twodirections (depending upon the direction of rod rotation) to effect thedesired transmission speed ratio drive connection. A pair of spacedcircumferential collars 3B and 3| located adjacent the base of rod iiireceive therebetwe'en the end of a lever 32 which is rotatably, mounted(not shown) adjacent its mid portion to some fixed object such as aportion of the vehicle body structure. A rod 33 connect lever 32 withtrans= mission selector lever l l. Axial movement of rod I9 istransmitted through this linkage to selector lever H.

An arm 35 is keyed to rod I9, as by a pin 36 and has connected to theouter end thereof a depending rod 35. A bifurcated lever 38 is rotatablymounted on a shaft 31 and one arm thereof is connected to rod 35. A rodll connects the other arm thereof to transmission shift lever I2.Rotation of rod 19 through the linkage just described rotates shiftlever I2 for manual transmission control.

Carburetor throttle lever l? is controlled by accelerator pedal l5through conventional linkage illustrated in Fig. 1. Rod H39 connected toaccelerator pedal I5 has its other end connected to lever i! keyed torotatably mounted shaft I02. A lever N33 is also keyed to shaft N12 forrotation therewith and rod ltd connects lever I93 with throttle leverll. Thus actuation of accelerator pedal I through rod lei], lever Hll,shaft I 62, lever H 3 and rod ltd rotates control lever I1.

In Fig. 1 automatic means have been superimposed on the manual controlsjust described. An air tight housing 48 containing a cylinder ll has atubular connection 52 with the engine intake manifold. A solenoid valve53 is adapted to selectively open and close this connection and ventcylinder M. A movable element in the form of a piston 44 is slidablymounted in cylinder ll and a spring 45 acting on piston M and reactingon housing 40 urges piston M to one end of cylinder 4|. Manifold lowpressure or vacuum as it is commonly referred to overcome spring 435when valve 53 is open. Piston rod $6 is connected to arm 41 which iskeyed to torque shaft 23. An ear ll on arm 6! is adapted to engage a lug.8 on collar 24. When cylinder ii i connected with the manifold throughvalve 43 and tubular passage 42 piston 44- is raised and piston rod 45rotates arm M in a counterclockwise direction. Ear 47 engages lug 48 oncollar 24 to rotate the collar and through lug 25 and rod 29 move clutchthrowout fork i l to disengage the clutch. The lost motion connection atslot 28 between rod 2? and clutch pedal l3 prevents the rotation ofcollar 24 from actuating the clutch pedal I3. When valve 43 closescylinder M to the manifold and vents the cylinder, spring 65 returns theparts described to their original position permitting the clutch toreengage.

The movement of piston At also effects changes in transmission speedratio drive. The apparatus i designed to actuate one shift railselectively in either of two directions. In the preferred form astandard transmission having a shift rail controlling second speed anddirect drive is controlled by movement of piston ts so that theapparatus herein automatically effects changes of speed ratio drivebetween a relatively slow drive of the driven wheels and a relativelyfast drive. Arm 50 is keyed to shaft 23 by pin 5d. An alternator,generally designated by the numeral 5| has a rod 52 operativelyconnected thereto. Alternator 5i is adapted to translatecounterclockwise rotation of arm 55 to alternate pushing and pullingmotion of rod 52. A support plate 53 is secured to a stationary object(not shown). A pin 55 projects from the surface of plate 53. A lever 56is fulcrumed at 56 on a bracket 57 supported by plate 53. A pair ofupwardly extending fingers 58 and 59 are rotatably mounted on lever 55on opposite sides of the fulcrum 58'. Spring to connecting fingers 58and 59 urges the fingers toward each other. The fingers 58 and 59 have arecessed portion with shoulders 63 adjacent the upper ends thereof. Abifurcated lever B l is rotatably connected to arm 50 and has a pin 65mounted on each fork thereof and adapted to engage shoulders 53. Pins 61and 62 guide the fingers and cooperate with the arcuate parts of theconnections of the fingers with lever 56 to direct the shoulder 63portion of the fingers toward the pin 55 when the finger occupies itshighest position in Fig. 1. A link 54 and bellcrank 55 transmit motionof lever 56 to rod 52. In the operation of the alternator with the partsin the positions shown in Fig. 1 downward motion of arm 50 will pulllever 64 downwardly and one pin 55 will push finger 58 downwardlythereby rotating lever 56 in a counterclockwise direction about fulcrum56' raising link 54, rotating bellcrank 65 and pulling rod 52 to theleft. With lever 55 in this position finger 59 has been raised and theportion thereof connected to lever 58 has been swung outwardly on an areabout the fulcrum 56' with the spring 60 urging the upper portionthereof to the left as far as pin $2 will permit in Fig. 1. When arm 56is raised the bifurcated lever is centered by the cam action of pin 55in the crotch thereof so that on its next downward movement the otherpin 65 engages shoulder 53 of finger 59 to reverse the movementsdescribed above to thereby push on rod 52. Through this mechanism eachsuccessive downward motion of arm 50 reverses the movement of rod 52.

Rod 52 is connected to the device which imparts resiliency to theconnection between rod 52 and the transmission control lever for thepurposes set forth above. Arm T0 is rotatably mounted on a shaft 37. Rod52 is connected to arm H3. A pin '53 is provided adjacent one end of thelever 35. The other end of lever 36 is bifurcated. Lever 36 isr-otatably mounted on the shaft 37 adjacent the lever crotch. Anabutment i2 is provided on lever 38 adjacent its bifurcated end. Aspring centered on pin 13 has arms 75 and 18 engaging opposite sides ofabutment l2 and engaging opposite sides of arm 70. One leg of lever 36is connected by rod 17 with transmission shift lever l2. The other legis connected by rod 35 to arm 3 of shift control rod [9. When alternator5i pulls on rod 52 arm is rotated clockwise compressing spring arm andlifting it away from abutment 12. Spring arm '56 is then no longer incontact with arm 70 and acts against abutment E2 to rotate lever 35about axis 31 until abutment I2 is aligned with rod 70 and therebymoving rod TI and lever [2 to the left. A similar but oppositelydirected motion is transmitted through the spring delay means whenalternator 5i pushes on rod 52. It should be noted that the spring isadapted to store force transmitted thereto by rod 52 until shift controllever and its associated synchronizer are able to utilize the force toeffect a change in transmission speed ratio drive. In addition,reference to the drawings shows a minimum thickness of the device alongthe axis of shaft 31. The presence of a spring does not increase thethickness of the device beyond the thickness of the arm and leverbecause of my novel arrangement of the component parts. This isimportant because the device is adapted to be installed adjacent avehicle engine or transmission where space is at a premium.

Means to control the actuation of piston will be referred to to completethe explanation of the operation of the illustrated apparatus. Agrounded source 89 of electric energy is connected through ignitionswitch 8! to a switch 82 by electrical conductor 83. Switch 82 isadapted to be closed when the rod [9 is placed in a predeterminedposition by the vehicle driver. This comprises the means by which thedriver selects automatic control. It is desirable to provide a clutchingmeans which will operatively disconnect the shift control rod 59 fromthe linkage when the driver selects automatic drive. This is desirableso that the shift control rod will not be moved by the automatic linkagemovement. This does not form a part of the invention and has not beenillustrated herein. Electrical line 85 connects switch 82 with a switch85 adapted to be closed when the throttle is substantially closed. Line86 connects switch 85 with a two-way shift rail switch 81 having afinger 88 thereon adapted to be engaged by abutments on an extension 89of the transmission second and high speed shift rail. A first circuit inswitch 87 is disconnected and a second circuit is connected when theshift rail has completed its shift. This switch movement alternates witheach transmission speed ratio change on the second and high speed shiftrail. A vehicle speed responsive governor 90 has one outlet terminal 9!and two inlet terminals 92 and 93 and is adapted to connect the outletterminal with one inlet terminal below a predetermined speed and withthe other inlet terminal above the predetermined speed. Each inletterminal is connected to one of the circuits referred to for switch Bl.Line 94 connects governor terminal 9| with solenoid valve 53 in manifoldline 42. Line 95 grounds the circuit. Valve 43 is adapted to connectcylinder 4! with the manifold line 42 when energized and to close line42 and vent cylinder t! to atmosphere when not energized.

In the operation of the apparatus when the driver closes the throttlelever l8 above a predetermined vehicle speed, valve ea is energized toadmit vacuum to cylinder M. Piston 44 is raised and clutch l disengagedthrough the linkage 46, M, ll, 2d, 25, 29, and Hi. This motion of thepiston also causes a delayed movement of transmission shift lever 12through arm 41, shaft 23, aternator 5!, rod 52, arm ill, lever 36, rod11, and shift lever I2. The change in speed ratio drive caused by movingshift lever l2 moves the shift rail extension as breaking the circuit atswitch 8? thereby deenergizing solenoid valve 43 and permitting spring45 to move piston 44 to the lower end of the cylinder and permitting theclutch to reengage. The switch 81 is new connected for its other circuitpreparatory to a repetition of the process when the driver closesthrottle lever ll below a predetermined governor speed. A transmissiondownshift is then effected in a manner similar to that described above.

Features of novelty disclosed but not claimed herein are moreparticularly described and claimed in the copending applications of CarlA. Neracher, Serial No. 661,298; Otto W. Schotz, Serial Nos. 687,248,698,451 and 755,661; and Maurice C. Robinson, Serial No, 755,612.

I claim:

1. In a motor vehicle control system adapted to change a transmissionspeed ratio drive, a movable element, means to move said element underselected vehicle operating conditions, an operative connection betweensaid element and said transmission, said connection including a firstlever rotatably mounted on an axis, a second lever rotatably mounted onsaid axis, a spring mounted on one of said levers on one side of saidactuation of said element stores energy in said spring to effect acushioned movement of said second lever to effect a change in speedratio drive in said transmission.

2. In a motor vehicle control system adapted to change a transmissionspeed ratio drive, a movable element, means to actuate said elementunder selected vehicle operating conditions, an operative connectionbetween said element and said transmission, said connection including afirst lever rotatably mounted on an axis, a second lever rotatablymounted on said axis, a spring mounted on one of said levers on one sideof said axis and reacting against the other of said levers on the otherside of said axis, said first lever being connected to said element onsaid other side of said axis and said second lever being connected tosaid transmission on said other side of said axis whereby said springtransmits motion from said element to said transmission through saidsecond lever.

3. In a control system for a motor vehicle variable speed ratiotransmission, a lever pivotally mounted on an axis, an operativeconnection of said lever to said transmission, a power shift mechanism,a second lever rotatably mounted on said axis and operatively connectedto said mechanism, a coil spring supported on a second axis andoperatively connecting said levers, whereby motion of said mechanism istransmitted through said spring to said transmission.

l. In a control system for a motor vehicle variable speed ratiotransmission, a lever .pivotally mounted on an axis, an operativeconnection of said lever to said transmission, a power shift mechanism,a second lever rotatably mounted on said axis and operatively connectedto said mechanism, both of said operative connections being located onone side of said axis, a spring mounted on one of said levers on theother side of said axis, extensions on said spring extending topositions adjacent said connections and abutting portions of said leverswhereby motion imparted to said second lever by said mechanism istransmitted to said first lever through said spring.

5. In a control system for a motor vehicle variable speed ratiotransmission, a lever pivotally mounted on an axis, an operativeconnection of said lever to said transmission, a power shift mechanism,a second lever rotatably mounted on said axis and operatively connectedto said mechanism, said levers being in close contact with each otheradjacent said axis and one of said levers having a portion extendingbeyond said other lever in one direction relative to said axis, a,spring mounted on said portion and having legs thereof engaging both ofsaid levers whereby a minimum of thickness along said axis is obtainedand whereby motion imparted to said second lever by said mechanism istransmitted to said first lever through said spring.

OTTO W. SCHOTZ.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,493,301 Walker May 6, 19242,136,023 Russell Nov. 8, 1938 2,397,883 Peterson et a1 Apr. 2, 19462,398,407 Brownyer Apr. 16, 1946 2,402,343 Price June 18, 1946

